/*
 * Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 */

package java.awt.font;

import java.io.IOException;
import java.io.ObjectOutputStream;
import java.util.Arrays;
import java.util.Comparator;
import java.util.EnumSet;
import java.util.Set;

/**
 * The <code>NumericShaper</code> class is used to convert Latin-1 (European)
 * digits to other Unicode decimal digits.  Users of this class will
 * primarily be people who wish to present data using
 * national digit shapes, but find it more convenient to represent the
 * data internally using Latin-1 (European) digits.  This does not
 * interpret the deprecated numeric shape selector character (U+206E).
 * <p>
 * Instances of <code>NumericShaper</code> are typically applied
 * as attributes to text with the
 * {@link TextAttribute#NUMERIC_SHAPING NUMERIC_SHAPING} attribute
 * of the <code>TextAttribute</code> class.
 * For example, this code snippet causes a <code>TextLayout</code> to
 * shape European digits to Arabic in an Arabic context:<br>
 * <blockquote><pre>
 * Map map = new HashMap();
 * map.put(TextAttribute.NUMERIC_SHAPING,
 *     NumericShaper.getContextualShaper(NumericShaper.ARABIC));
 * FontRenderContext frc = ...;
 * TextLayout layout = new TextLayout(text, map, frc);
 * layout.draw(g2d, x, y);
 * </pre></blockquote>
 * <br>
 * It is also possible to perform numeric shaping explicitly using instances
 * of <code>NumericShaper</code>, as this code snippet demonstrates:<br>
 * <blockquote><pre>
 * char[] text = ...;
 * // shape all EUROPEAN digits (except zero) to ARABIC digits
 * NumericShaper shaper = NumericShaper.getShaper(NumericShaper.ARABIC);
 * shaper.shape(text, start, count);
 *
 * // shape European digits to ARABIC digits if preceding text is Arabic, or
 * // shape European digits to TAMIL digits if preceding text is Tamil, or
 * // leave European digits alone if there is no preceding text, or
 * // preceding text is neither Arabic nor Tamil
 * NumericShaper shaper =
 *     NumericShaper.getContextualShaper(NumericShaper.ARABIC |
 *                                         NumericShaper.TAMIL,
 *                                       NumericShaper.EUROPEAN);
 * shaper.shape(text, start, count);
 * </pre></blockquote>
 *
 * <p><b>Bit mask- and enum-based Unicode ranges</b></p>
 *
 * <p>This class supports two different programming interfaces to
 * represent Unicode ranges for script-specific digits: bit
 * mask-based ones, such as {@link #ARABIC NumericShaper.ARABIC}, and
 * enum-based ones, such as {@link NumericShaper.Range#ARABIC}.
 * Multiple ranges can be specified by ORing bit mask-based constants,
 * such as:
 * <blockquote><pre>
 * NumericShaper.ARABIC | NumericShaper.TAMIL
 * </pre></blockquote>
 * or creating a {@code Set} with the {@link NumericShaper.Range}
 * constants, such as:
 * <blockquote><pre>
 * EnumSet.of(NumericShaper.Scirpt.ARABIC, NumericShaper.Range.TAMIL)
 * </pre></blockquote>
 * The enum-based ranges are a super set of the bit mask-based ones.
 *
 * <p>If the two interfaces are mixed (including serialization),
 * Unicode range values are mapped to their counterparts where such
 * mapping is possible, such as {@code NumericShaper.Range.ARABIC}
 * from/to {@code NumericShaper.ARABIC}.  If any unmappable range
 * values are specified, such as {@code NumericShaper.Range.BALINESE},
 * those ranges are ignored.
 *
 * <p><b>Decimal Digits Precedence</b></p>
 *
 * <p>A Unicode range may have more than one set of decimal digits. If
 * multiple decimal digits sets are specified for the same Unicode
 * range, one of the sets will take precedence as follows.
 *
 * <table border=1 cellspacing=3 cellpadding=0 summary="NumericShaper constants precedence.">
 *    <tr>
 *       <th class="TableHeadingColor">Unicode Range</th>
 *       <th class="TableHeadingColor"><code>NumericShaper</code> Constants</th>
 *       <th class="TableHeadingColor">Precedence</th>
 *    </tr>
 *    <tr>
 *       <td rowspan="2">Arabic</td>
 *       <td>{@link NumericShaper#ARABIC NumericShaper.ARABIC}<br>
 *           {@link NumericShaper#EASTERN_ARABIC NumericShaper.EASTERN_ARABIC}</td>
 *       <td>{@link NumericShaper#EASTERN_ARABIC NumericShaper.EASTERN_ARABIC}</td>
 *    </tr>
 *    <tr>
 *       <td>{@link NumericShaper.Range#ARABIC}<br>
 *           {@link NumericShaper.Range#EASTERN_ARABIC}</td>
 *       <td>{@link NumericShaper.Range#EASTERN_ARABIC}</td>
 *    </tr>
 *    <tr>
 *       <td>Tai Tham</td>
 *       <td>{@link NumericShaper.Range#TAI_THAM_HORA}<br>
 *           {@link NumericShaper.Range#TAI_THAM_THAM}</td>
 *       <td>{@link NumericShaper.Range#TAI_THAM_THAM}</td>
 *    </tr>
 * </table>
 *
 * @since 1.4
 */

public final class NumericShaper implements java.io.Serializable {
    /**
     * A {@code NumericShaper.Range} represents a Unicode range of a
     * script having its own decimal digits. For example, the {@link
     * NumericShaper.Range#THAI} range has the Thai digits, THAI DIGIT
     * ZERO (U+0E50) to THAI DIGIT NINE (U+0E59).
     *
     * <p>The <code>Range</code> enum replaces the traditional bit
     * mask-based values (e.g., {@link NumericShaper#ARABIC}), and
     * supports more Unicode ranges than the bit mask-based ones. For
     * example, the following code using the bit mask:
     * <blockquote><pre>
     * NumericShaper.getContextualShaper(NumericShaper.ARABIC |
     *                                     NumericShaper.TAMIL,
     *                                   NumericShaper.EUROPEAN);
     * </pre></blockquote>
     * can be written using this enum as:
     * <blockquote><pre>
     * NumericShaper.getContextualShaper(EnumSet.of(
     *                                     NumericShaper.Range.ARABIC,
     *                                     NumericShaper.Range.TAMIL),
     *                                   NumericShaper.Range.EUROPEAN);
     * </pre></blockquote>
     *
     * @since 1.7
     */
    public static enum Range {
        // The order of EUROPEAN to MOGOLIAN must be consistent
        // with the bitmask-based constants.
        /**
         * The Latin (European) range with the Latin (ASCII) digits.
         */
        EUROPEAN('\u0030', '\u0000', '\u0300'),
        /**
         * The Arabic range with the Arabic-Indic digits.
         */
        ARABIC('\u0660', '\u0600', '\u0780'),
        /**
         * The Arabic range with the Eastern Arabic-Indic digits.
         */
        EASTERN_ARABIC('\u06f0', '\u0600', '\u0780'),
        /**
         * The Devanagari range with the Devanagari digits.
         */
        DEVANAGARI('\u0966', '\u0900', '\u0980'),
        /**
         * The Bengali range with the Bengali digits.
         */
        BENGALI('\u09e6', '\u0980', '\u0a00'),
        /**
         * The Gurmukhi range with the Gurmukhi digits.
         */
        GURMUKHI('\u0a66', '\u0a00', '\u0a80'),
        /**
         * The Gujarati range with the Gujarati digits.
         */
        GUJARATI('\u0ae6', '\u0b00', '\u0b80'),
        /**
         * The Oriya range with the Oriya digits.
         */
        ORIYA('\u0b66', '\u0b00', '\u0b80'),
        /**
         * The Tamil range with the Tamil digits.
         */
        TAMIL('\u0be6', '\u0b80', '\u0c00'),
        /**
         * The Telugu range with the Telugu digits.
         */
        TELUGU('\u0c66', '\u0c00', '\u0c80'),
        /**
         * The Kannada range with the Kannada digits.
         */
        KANNADA('\u0ce6', '\u0c80', '\u0d00'),
        /**
         * The Malayalam range with the Malayalam digits.
         */
        MALAYALAM('\u0d66', '\u0d00', '\u0d80'),
        /**
         * The Thai range with the Thai digits.
         */
        THAI('\u0e50', '\u0e00', '\u0e80'),
        /**
         * The Lao range with the Lao digits.
         */
        LAO('\u0ed0', '\u0e80', '\u0f00'),
        /**
         * The Tibetan range with the Tibetan digits.
         */
        TIBETAN('\u0f20', '\u0f00', '\u1000'),
        /**
         * The Myanmar range with the Myanmar digits.
         */
        MYANMAR('\u1040', '\u1000', '\u1080'),
        /**
         * The Ethiopic range with the Ethiopic digits. Ethiopic
         * does not have a decimal digit 0 so Latin (European) 0 is
         * used.
         */
        ETHIOPIC('\u1369', '\u1200', '\u1380') {
            @Override
            char getNumericBase() {
                return 1;
            }
        },
        /**
         * The Khmer range with the Khmer digits.
         */
        KHMER('\u17e0', '\u1780', '\u1800'),
        /**
         * The Mongolian range with the Mongolian digits.
         */
        MONGOLIAN('\u1810', '\u1800', '\u1900'),
        // The order of EUROPEAN to MOGOLIAN must be consistent
        // with the bitmask-based constants.

        /**
         * The N'Ko range with the N'Ko digits.
         */
        NKO('\u07c0', '\u07c0', '\u0800'),
        /**
         * The Myanmar range with the Myanmar Shan digits.
         */
        MYANMAR_SHAN('\u1090', '\u1000', '\u10a0'),
        /**
         * The Limbu range with the Limbu digits.
         */
        LIMBU('\u1946', '\u1900', '\u1950'),
        /**
         * The New Tai Lue range with the New Tai Lue digits.
         */
        NEW_TAI_LUE('\u19d0', '\u1980', '\u19e0'),
        /**
         * The Balinese range with the Balinese digits.
         */
        BALINESE('\u1b50', '\u1b00', '\u1b80'),
        /**
         * The Sundanese range with the Sundanese digits.
         */
        SUNDANESE('\u1bb0', '\u1b80', '\u1bc0'),
        /**
         * The Lepcha range with the Lepcha digits.
         */
        LEPCHA('\u1c40', '\u1c00', '\u1c50'),
        /**
         * The Ol Chiki range with the Ol Chiki digits.
         */
        OL_CHIKI('\u1c50', '\u1c50', '\u1c80'),
        /**
         * The Vai range with the Vai digits.
         */
        VAI('\ua620', '\ua500', '\ua640'),
        /**
         * The Saurashtra range with the Saurashtra digits.
         */
        SAURASHTRA('\ua8d0', '\ua880', '\ua8e0'),
        /**
         * The Kayah Li range with the Kayah Li digits.
         */
        KAYAH_LI('\ua900', '\ua900', '\ua930'),
        /**
         * The Cham range with the Cham digits.
         */
        CHAM('\uaa50', '\uaa00', '\uaa60'),
        /**
         * The Tai Tham Hora range with the Tai Tham Hora digits.
         */
        TAI_THAM_HORA('\u1a80', '\u1a20', '\u1ab0'),
        /**
         * The Tai Tham Tham range with the Tai Tham Tham digits.
         */
        TAI_THAM_THAM('\u1a90', '\u1a20', '\u1ab0'),
        /**
         * The Javanese range with the Javanese digits.
         */
        JAVANESE('\ua9d0', '\ua980', '\ua9e0'),
        /**
         * The Meetei Mayek range with the Meetei Mayek digits.
         */
        MEETEI_MAYEK('\uabf0', '\uabc0', '\uac00');

        private static int toRangeIndex(Range script) {
            int index = script.ordinal();
            return index < NUM_KEYS ? index : -1;
        }

        private static Range indexToRange(int index) {
            return index < NUM_KEYS ? Range.values()[index] : null;
        }

        private static int toRangeMask(Set<Range> ranges) {
            int m = 0;
            for (Range range : ranges) {
                int index = range.ordinal();
                if (index < NUM_KEYS) {
                    m |= 1 << index;
                }
            }
            return m;
        }

        private static Set<Range> maskToRangeSet(int mask) {
            Set<Range> set = EnumSet.noneOf(Range.class);
            Range[] a = Range.values();
            for (int i = 0; i < NUM_KEYS; i++) {
                if ((mask & (1 << i)) != 0) {
                    set.add(a[i]);
                }
            }
            return set;
        }

        // base character of range digits
        private final int base;
        // Unicode range
        private final int start, // inclusive
                end;   // exclusive

        private Range(int base, int start, int end) {
            this.base = base - ('0' + getNumericBase());
            this.start = start;
            this.end = end;
        }

        private int getDigitBase() {
            return base;
        }

        char getNumericBase() {
            return 0;
        }

        private boolean inRange(int c) {
            return start <= c && c < end;
        }
    }

    /**
     * index of context for contextual shaping - values range from 0 to 18
     */
    private int key;

    /**
     * flag indicating whether to shape contextually (high bit) and which
     * digit ranges to shape (bits 0-18)
     */
    private int mask;

    /**
     * The context {@code Range} for contextual shaping or the {@code
     * Range} for non-contextual shaping. {@code null} for the bit
     * mask-based API.
     *
     * @since 1.7
     */
    private Range shapingRange;

    /**
     * {@code Set<Range>} indicating which Unicode ranges to
     * shape. {@code null} for the bit mask-based API.
     */
    private transient Set<Range> rangeSet;

    /**
     * rangeSet.toArray() value. Sorted by Range.base when the number
     * of elements is greater then BSEARCH_THRESHOLD.
     */
    private transient Range[] rangeArray;

    /**
     * If more than BSEARCH_THRESHOLD ranges are specified, binary search is used.
     */
    private static final int BSEARCH_THRESHOLD = 3;

    private static final long serialVersionUID = -8022764705923730308L;

    /**
     * Identifies the Latin-1 (European) and extended range, and
     * Latin-1 (European) decimal base.
     */
    public static final int EUROPEAN = 1 << 0;

    /**
     * Identifies the ARABIC range and decimal base.
     */
    public static final int ARABIC = 1 << 1;

    /**
     * Identifies the ARABIC range and ARABIC_EXTENDED decimal base.
     */
    public static final int EASTERN_ARABIC = 1 << 2;

    /**
     * Identifies the DEVANAGARI range and decimal base.
     */
    public static final int DEVANAGARI = 1 << 3;

    /**
     * Identifies the BENGALI range and decimal base.
     */
    public static final int BENGALI = 1 << 4;

    /**
     * Identifies the GURMUKHI range and decimal base.
     */
    public static final int GURMUKHI = 1 << 5;

    /**
     * Identifies the GUJARATI range and decimal base.
     */
    public static final int GUJARATI = 1 << 6;

    /**
     * Identifies the ORIYA range and decimal base.
     */
    public static final int ORIYA = 1 << 7;

    /**
     * Identifies the TAMIL range and decimal base.
     */
    // TAMIL DIGIT ZERO was added in Unicode 4.1
    public static final int TAMIL = 1 << 8;

    /**
     * Identifies the TELUGU range and decimal base.
     */
    public static final int TELUGU = 1 << 9;

    /**
     * Identifies the KANNADA range and decimal base.
     */
    public static final int KANNADA = 1 << 10;

    /**
     * Identifies the MALAYALAM range and decimal base.
     */
    public static final int MALAYALAM = 1 << 11;

    /**
     * Identifies the THAI range and decimal base.
     */
    public static final int THAI = 1 << 12;

    /**
     * Identifies the LAO range and decimal base.
     */
    public static final int LAO = 1 << 13;

    /**
     * Identifies the TIBETAN range and decimal base.
     */
    public static final int TIBETAN = 1 << 14;

    /**
     * Identifies the MYANMAR range and decimal base.
     */
    public static final int MYANMAR = 1 << 15;

    /**
     * Identifies the ETHIOPIC range and decimal base.
     */
    public static final int ETHIOPIC = 1 << 16;

    /**
     * Identifies the KHMER range and decimal base.
     */
    public static final int KHMER = 1 << 17;

    /**
     * Identifies the MONGOLIAN range and decimal base.
     */
    public static final int MONGOLIAN = 1 << 18;

    /**
     * Identifies all ranges, for full contextual shaping.
     *
     * <p>This constant specifies all of the bit mask-based
     * ranges. Use {@code EmunSet.allOf(NumericShaper.Range.class)} to
     * specify all of the enum-based ranges.
     */
    public static final int ALL_RANGES = 0x0007ffff;

    private static final int EUROPEAN_KEY = 0;
    private static final int ARABIC_KEY = 1;
    private static final int EASTERN_ARABIC_KEY = 2;
    private static final int DEVANAGARI_KEY = 3;
    private static final int BENGALI_KEY = 4;
    private static final int GURMUKHI_KEY = 5;
    private static final int GUJARATI_KEY = 6;
    private static final int ORIYA_KEY = 7;
    private static final int TAMIL_KEY = 8;
    private static final int TELUGU_KEY = 9;
    private static final int KANNADA_KEY = 10;
    private static final int MALAYALAM_KEY = 11;
    private static final int THAI_KEY = 12;
    private static final int LAO_KEY = 13;
    private static final int TIBETAN_KEY = 14;
    private static final int MYANMAR_KEY = 15;
    private static final int ETHIOPIC_KEY = 16;
    private static final int KHMER_KEY = 17;
    private static final int MONGOLIAN_KEY = 18;

    private static final int NUM_KEYS = MONGOLIAN_KEY + 1; // fixed

    private static final int CONTEXTUAL_MASK = 1 << 31;

    private static final char[] bases = {
            '\u0030' - '\u0030', // EUROPEAN
            '\u0660' - '\u0030', // ARABIC-INDIC
            '\u06f0' - '\u0030', // EXTENDED ARABIC-INDIC (EASTERN_ARABIC)
            '\u0966' - '\u0030', // DEVANAGARI
            '\u09e6' - '\u0030', // BENGALI
            '\u0a66' - '\u0030', // GURMUKHI
            '\u0ae6' - '\u0030', // GUJARATI
            '\u0b66' - '\u0030', // ORIYA
            '\u0be6' - '\u0030', // TAMIL - zero was added in Unicode 4.1
            '\u0c66' - '\u0030', // TELUGU
            '\u0ce6' - '\u0030', // KANNADA
            '\u0d66' - '\u0030', // MALAYALAM
            '\u0e50' - '\u0030', // THAI
            '\u0ed0' - '\u0030', // LAO
            '\u0f20' - '\u0030', // TIBETAN
            '\u1040' - '\u0030', // MYANMAR
            '\u1369' - '\u0031', // ETHIOPIC - no zero
            '\u17e0' - '\u0030', // KHMER
            '\u1810' - '\u0030', // MONGOLIAN
    };

    // some ranges adjoin or overlap, rethink if we want to do a binary search on this

    private static final char[] contexts = {
            '\u0000', '\u0300', // 'EUROPEAN' (really latin-1 and extended)
            '\u0600', '\u0780', // ARABIC
            '\u0600', '\u0780', // EASTERN_ARABIC -- note overlap with arabic
            '\u0900', '\u0980', // DEVANAGARI
            '\u0980', '\u0a00', // BENGALI
            '\u0a00', '\u0a80', // GURMUKHI
            '\u0a80', '\u0b00', // GUJARATI
            '\u0b00', '\u0b80', // ORIYA
            '\u0b80', '\u0c00', // TAMIL
            '\u0c00', '\u0c80', // TELUGU
            '\u0c80', '\u0d00', // KANNADA
            '\u0d00', '\u0d80', // MALAYALAM
            '\u0e00', '\u0e80', // THAI
            '\u0e80', '\u0f00', // LAO
            '\u0f00', '\u1000', // TIBETAN
            '\u1000', '\u1080', // MYANMAR
            '\u1200', '\u1380', // ETHIOPIC - note missing zero
            '\u1780', '\u1800', // KHMER
            '\u1800', '\u1900', // MONGOLIAN
            '\uffff',
    };

    // assume most characters are near each other so probing the cache is infrequent,
    // and a linear probe is ok.

    private static int ctCache = 0;
    private static int ctCacheLimit = contexts.length - 2;

    // warning, synchronize access to this as it modifies state
    private static int getContextKey(char c) {
        if (c < contexts[ctCache]) {
            while (ctCache > 0 && c < contexts[ctCache]) --ctCache;
        } else if (c >= contexts[ctCache + 1]) {
            while (ctCache < ctCacheLimit && c >= contexts[ctCache + 1]) ++ctCache;
        }

        // if we're not in a known range, then return EUROPEAN as the range key
        return (ctCache & 0x1) == 0 ? (ctCache / 2) : EUROPEAN_KEY;
    }

    // cache for the NumericShaper.Range version
    private transient volatile Range currentRange = Range.EUROPEAN;

    private Range rangeForCodePoint(final int codepoint) {
        if (currentRange.inRange(codepoint)) {
            return currentRange;
        }

        final Range[] ranges = rangeArray;
        if (ranges.length > BSEARCH_THRESHOLD) {
            int lo = 0;
            int hi = ranges.length - 1;
            while (lo <= hi) {
                int mid = (lo + hi) / 2;
                Range range = ranges[mid];
                if (codepoint < range.start) {
                    hi = mid - 1;
                } else if (codepoint >= range.end) {
                    lo = mid + 1;
                } else {
                    currentRange = range;
                    return range;
                }
            }
        } else {
            for (int i = 0; i < ranges.length; i++) {
                if (ranges[i].inRange(codepoint)) {
                    return ranges[i];
                }
            }
        }
        return Range.EUROPEAN;
    }

    /*
     * A range table of strong directional characters (types L, R, AL).
     * Even (left) indexes are starts of ranges of non-strong-directional (or undefined)
     * characters, odd (right) indexes are starts of ranges of strong directional
     * characters.
     */
    private static int[] strongTable = {
            0x0000, 0x0041,
            0x005b, 0x0061,
            0x007b, 0x00aa,
            0x00ab, 0x00b5,
            0x00b6, 0x00ba,
            0x00bb, 0x00c0,
            0x00d7, 0x00d8,
            0x00f7, 0x00f8,
            0x02b9, 0x02bb,
            0x02c2, 0x02d0,
            0x02d2, 0x02e0,
            0x02e5, 0x02ee,
            0x02ef, 0x0370,
            0x0374, 0x0376,
            0x037e, 0x0386,
            0x0387, 0x0388,
            0x03f6, 0x03f7,
            0x0483, 0x048a,
            0x058a, 0x05be,
            0x05bf, 0x05c0,
            0x05c1, 0x05c3,
            0x05c4, 0x05c6,
            0x05c7, 0x05d0,
            0x0600, 0x0608,
            0x0609, 0x060b,
            0x060c, 0x060d,
            0x060e, 0x061b,
            0x064b, 0x066d,
            0x0670, 0x0671,
            0x06d6, 0x06e5,
            0x06e7, 0x06ee,
            0x06f0, 0x06fa,
            0x0711, 0x0712,
            0x0730, 0x074d,
            0x07a6, 0x07b1,
            0x07eb, 0x07f4,
            0x07f6, 0x07fa,
            0x0816, 0x081a,
            0x081b, 0x0824,
            0x0825, 0x0828,
            0x0829, 0x0830,
            0x0859, 0x085e,
            0x08e4, 0x0903,
            0x093a, 0x093b,
            0x093c, 0x093d,
            0x0941, 0x0949,
            0x094d, 0x094e,
            0x0951, 0x0958,
            0x0962, 0x0964,
            0x0981, 0x0982,
            0x09bc, 0x09bd,
            0x09c1, 0x09c7,
            0x09cd, 0x09ce,
            0x09e2, 0x09e6,
            0x09f2, 0x09f4,
            0x09fb, 0x0a03,
            0x0a3c, 0x0a3e,
            0x0a41, 0x0a59,
            0x0a70, 0x0a72,
            0x0a75, 0x0a83,
            0x0abc, 0x0abd,
            0x0ac1, 0x0ac9,
            0x0acd, 0x0ad0,
            0x0ae2, 0x0ae6,
            0x0af1, 0x0b02,
            0x0b3c, 0x0b3d,
            0x0b3f, 0x0b40,
            0x0b41, 0x0b47,
            0x0b4d, 0x0b57,
            0x0b62, 0x0b66,
            0x0b82, 0x0b83,
            0x0bc0, 0x0bc1,
            0x0bcd, 0x0bd0,
            0x0bf3, 0x0c01,
            0x0c3e, 0x0c41,
            0x0c46, 0x0c58,
            0x0c62, 0x0c66,
            0x0c78, 0x0c7f,
            0x0cbc, 0x0cbd,
            0x0ccc, 0x0cd5,
            0x0ce2, 0x0ce6,
            0x0d41, 0x0d46,
            0x0d4d, 0x0d4e,
            0x0d62, 0x0d66,
            0x0dca, 0x0dcf,
            0x0dd2, 0x0dd8,
            0x0e31, 0x0e32,
            0x0e34, 0x0e40,
            0x0e47, 0x0e4f,
            0x0eb1, 0x0eb2,
            0x0eb4, 0x0ebd,
            0x0ec8, 0x0ed0,
            0x0f18, 0x0f1a,
            0x0f35, 0x0f36,
            0x0f37, 0x0f38,
            0x0f39, 0x0f3e,
            0x0f71, 0x0f7f,
            0x0f80, 0x0f85,
            0x0f86, 0x0f88,
            0x0f8d, 0x0fbe,
            0x0fc6, 0x0fc7,
            0x102d, 0x1031,
            0x1032, 0x1038,
            0x1039, 0x103b,
            0x103d, 0x103f,
            0x1058, 0x105a,
            0x105e, 0x1061,
            0x1071, 0x1075,
            0x1082, 0x1083,
            0x1085, 0x1087,
            0x108d, 0x108e,
            0x109d, 0x109e,
            0x135d, 0x1360,
            0x1390, 0x13a0,
            0x1400, 0x1401,
            0x1680, 0x1681,
            0x169b, 0x16a0,
            0x1712, 0x1720,
            0x1732, 0x1735,
            0x1752, 0x1760,
            0x1772, 0x1780,
            0x17b4, 0x17b6,
            0x17b7, 0x17be,
            0x17c6, 0x17c7,
            0x17c9, 0x17d4,
            0x17db, 0x17dc,
            0x17dd, 0x17e0,
            0x17f0, 0x1810,
            0x18a9, 0x18aa,
            0x1920, 0x1923,
            0x1927, 0x1929,
            0x1932, 0x1933,
            0x1939, 0x1946,
            0x19de, 0x1a00,
            0x1a17, 0x1a19,
            0x1a56, 0x1a57,
            0x1a58, 0x1a61,
            0x1a62, 0x1a63,
            0x1a65, 0x1a6d,
            0x1a73, 0x1a80,
            0x1b00, 0x1b04,
            0x1b34, 0x1b35,
            0x1b36, 0x1b3b,
            0x1b3c, 0x1b3d,
            0x1b42, 0x1b43,
            0x1b6b, 0x1b74,
            0x1b80, 0x1b82,
            0x1ba2, 0x1ba6,
            0x1ba8, 0x1baa,
            0x1bab, 0x1bac,
            0x1be6, 0x1be7,
            0x1be8, 0x1bea,
            0x1bed, 0x1bee,
            0x1bef, 0x1bf2,
            0x1c2c, 0x1c34,
            0x1c36, 0x1c3b,
            0x1cd0, 0x1cd3,
            0x1cd4, 0x1ce1,
            0x1ce2, 0x1ce9,
            0x1ced, 0x1cee,
            0x1cf4, 0x1cf5,
            0x1dc0, 0x1e00,
            0x1fbd, 0x1fbe,
            0x1fbf, 0x1fc2,
            0x1fcd, 0x1fd0,
            0x1fdd, 0x1fe0,
            0x1fed, 0x1ff2,
            0x1ffd, 0x200e,
            0x2010, 0x2071,
            0x2074, 0x207f,
            0x2080, 0x2090,
            0x20a0, 0x2102,
            0x2103, 0x2107,
            0x2108, 0x210a,
            0x2114, 0x2115,
            0x2116, 0x2119,
            0x211e, 0x2124,
            0x2125, 0x2126,
            0x2127, 0x2128,
            0x2129, 0x212a,
            0x212e, 0x212f,
            0x213a, 0x213c,
            0x2140, 0x2145,
            0x214a, 0x214e,
            0x2150, 0x2160,
            0x2189, 0x2336,
            0x237b, 0x2395,
            0x2396, 0x249c,
            0x24ea, 0x26ac,
            0x26ad, 0x2800,
            0x2900, 0x2c00,
            0x2ce5, 0x2ceb,
            0x2cef, 0x2cf2,
            0x2cf9, 0x2d00,
            0x2d7f, 0x2d80,
            0x2de0, 0x3005,
            0x3008, 0x3021,
            0x302a, 0x3031,
            0x3036, 0x3038,
            0x303d, 0x3041,
            0x3099, 0x309d,
            0x30a0, 0x30a1,
            0x30fb, 0x30fc,
            0x31c0, 0x31f0,
            0x321d, 0x3220,
            0x3250, 0x3260,
            0x327c, 0x327f,
            0x32b1, 0x32c0,
            0x32cc, 0x32d0,
            0x3377, 0x337b,
            0x33de, 0x33e0,
            0x33ff, 0x3400,
            0x4dc0, 0x4e00,
            0xa490, 0xa4d0,
            0xa60d, 0xa610,
            0xa66f, 0xa680,
            0xa69f, 0xa6a0,
            0xa6f0, 0xa6f2,
            0xa700, 0xa722,
            0xa788, 0xa789,
            0xa802, 0xa803,
            0xa806, 0xa807,
            0xa80b, 0xa80c,
            0xa825, 0xa827,
            0xa828, 0xa830,
            0xa838, 0xa840,
            0xa874, 0xa880,
            0xa8c4, 0xa8ce,
            0xa8e0, 0xa8f2,
            0xa926, 0xa92e,
            0xa947, 0xa952,
            0xa980, 0xa983,
            0xa9b3, 0xa9b4,
            0xa9b6, 0xa9ba,
            0xa9bc, 0xa9bd,
            0xaa29, 0xaa2f,
            0xaa31, 0xaa33,
            0xaa35, 0xaa40,
            0xaa43, 0xaa44,
            0xaa4c, 0xaa4d,
            0xaab0, 0xaab1,
            0xaab2, 0xaab5,
            0xaab7, 0xaab9,
            0xaabe, 0xaac0,
            0xaac1, 0xaac2,
            0xaaec, 0xaaee,
            0xaaf6, 0xab01,
            0xabe5, 0xabe6,
            0xabe8, 0xabe9,
            0xabed, 0xabf0,
            0xfb1e, 0xfb1f,
            0xfb29, 0xfb2a,
            0xfd3e, 0xfd50,
            0xfdfd, 0xfe70,
            0xfeff, 0xff21,
            0xff3b, 0xff41,
            0xff5b, 0xff66,
            0xffe0, 0x10000,
            0x10101, 0x10102,
            0x10140, 0x101d0,
            0x101fd, 0x10280,
            0x1091f, 0x10920,
            0x10a01, 0x10a10,
            0x10a38, 0x10a40,
            0x10b39, 0x10b40,
            0x10e60, 0x11000,
            0x11001, 0x11002,
            0x11038, 0x11047,
            0x11052, 0x11066,
            0x11080, 0x11082,
            0x110b3, 0x110b7,
            0x110b9, 0x110bb,
            0x11100, 0x11103,
            0x11127, 0x1112c,
            0x1112d, 0x11136,
            0x11180, 0x11182,
            0x111b6, 0x111bf,
            0x116ab, 0x116ac,
            0x116ad, 0x116ae,
            0x116b0, 0x116b6,
            0x116b7, 0x116c0,
            0x16f8f, 0x16f93,
            0x1d167, 0x1d16a,
            0x1d173, 0x1d183,
            0x1d185, 0x1d18c,
            0x1d1aa, 0x1d1ae,
            0x1d200, 0x1d360,
            0x1d6db, 0x1d6dc,
            0x1d715, 0x1d716,
            0x1d74f, 0x1d750,
            0x1d789, 0x1d78a,
            0x1d7c3, 0x1d7c4,
            0x1d7ce, 0x1ee00,
            0x1eef0, 0x1f110,
            0x1f16a, 0x1f170,
            0x1f300, 0x1f48c,
            0x1f48d, 0x1f524,
            0x1f525, 0x20000,
            0xe0001, 0xf0000,
            0x10fffe, 0x10ffff // sentinel
    };


    // use a binary search with a cache

    private transient volatile int stCache = 0;

    private boolean isStrongDirectional(char c) {
        int cachedIndex = stCache;
        if (c < strongTable[cachedIndex]) {
            cachedIndex = search(c, strongTable, 0, cachedIndex);
        } else if (c >= strongTable[cachedIndex + 1]) {
            cachedIndex = search(c, strongTable, cachedIndex + 1,
                    strongTable.length - cachedIndex - 1);
        }
        boolean val = (cachedIndex & 0x1) == 1;
        stCache = cachedIndex;
        return val;
    }

    private static int getKeyFromMask(int mask) {
        int key = 0;
        while (key < NUM_KEYS && ((mask & (1 << key)) == 0)) {
            ++key;
        }
        if (key == NUM_KEYS || ((mask & ~(1 << key)) != 0)) {
            throw new IllegalArgumentException("invalid shaper: " + Integer.toHexString(mask));
        }
        return key;
    }

    /**
     * Returns a shaper for the provided unicode range.  All
     * Latin-1 (EUROPEAN) digits are converted
     * to the corresponding decimal unicode digits.
     *
     * @param singleRange the specified Unicode range
     * @return a non-contextual numeric shaper
     * @throws IllegalArgumentException if the range is not a single range
     */
    public static NumericShaper getShaper(int singleRange) {
        int key = getKeyFromMask(singleRange);
        return new NumericShaper(key, singleRange);
    }

    /**
     * Returns a shaper for the provided Unicode
     * range. All Latin-1 (EUROPEAN) digits are converted to the
     * corresponding decimal digits of the specified Unicode range.
     *
     * @param singleRange the Unicode range given by a {@link
     *                    NumericShaper.Range} constant.
     * @return a non-contextual {@code NumericShaper}.
     * @throws NullPointerException if {@code singleRange} is {@code null}
     * @since 1.7
     */
    public static NumericShaper getShaper(Range singleRange) {
        return new NumericShaper(singleRange, EnumSet.of(singleRange));
    }

    /**
     * Returns a contextual shaper for the provided unicode range(s).
     * Latin-1 (EUROPEAN) digits are converted to the decimal digits
     * corresponding to the range of the preceding text, if the
     * range is one of the provided ranges.  Multiple ranges are
     * represented by or-ing the values together, such as,
     * <code>NumericShaper.ARABIC | NumericShaper.THAI</code>.  The
     * shaper assumes EUROPEAN as the starting context, that is, if
     * EUROPEAN digits are encountered before any strong directional
     * text in the string, the context is presumed to be EUROPEAN, and
     * so the digits will not shape.
     *
     * @param ranges the specified Unicode ranges
     * @return a shaper for the specified ranges
     */
    public static NumericShaper getContextualShaper(int ranges) {
        ranges |= CONTEXTUAL_MASK;
        return new NumericShaper(EUROPEAN_KEY, ranges);
    }

    /**
     * Returns a contextual shaper for the provided Unicode
     * range(s). The Latin-1 (EUROPEAN) digits are converted to the
     * decimal digits corresponding to the range of the preceding
     * text, if the range is one of the provided ranges.
     *
     * <p>The shaper assumes EUROPEAN as the starting context, that
     * is, if EUROPEAN digits are encountered before any strong
     * directional text in the string, the context is presumed to be
     * EUROPEAN, and so the digits will not shape.
     *
     * @param ranges the specified Unicode ranges
     * @return a contextual shaper for the specified ranges
     * @throws NullPointerException if {@code ranges} is {@code null}.
     * @since 1.7
     */
    public static NumericShaper getContextualShaper(Set<Range> ranges) {
        NumericShaper shaper = new NumericShaper(Range.EUROPEAN, ranges);
        shaper.mask = CONTEXTUAL_MASK;
        return shaper;
    }

    /**
     * Returns a contextual shaper for the provided unicode range(s).
     * Latin-1 (EUROPEAN) digits will be converted to the decimal digits
     * corresponding to the range of the preceding text, if the
     * range is one of the provided ranges.  Multiple ranges are
     * represented by or-ing the values together, for example,
     * <code>NumericShaper.ARABIC | NumericShaper.THAI</code>.  The
     * shaper uses defaultContext as the starting context.
     *
     * @param ranges         the specified Unicode ranges
     * @param defaultContext the starting context, such as
     *                       <code>NumericShaper.EUROPEAN</code>
     * @return a shaper for the specified Unicode ranges.
     * @throws IllegalArgumentException if the specified
     *                                  <code>defaultContext</code> is not a single valid range.
     */
    public static NumericShaper getContextualShaper(int ranges, int defaultContext) {
        int key = getKeyFromMask(defaultContext);
        ranges |= CONTEXTUAL_MASK;
        return new NumericShaper(key, ranges);
    }

    /**
     * Returns a contextual shaper for the provided Unicode range(s).
     * The Latin-1 (EUROPEAN) digits will be converted to the decimal
     * digits corresponding to the range of the preceding text, if the
     * range is one of the provided ranges. The shaper uses {@code
     * defaultContext} as the starting context.
     *
     * @param ranges         the specified Unicode ranges
     * @param defaultContext the starting context, such as
     *                       {@code NumericShaper.Range.EUROPEAN}
     * @return a contextual shaper for the specified Unicode ranges.
     * @throws NullPointerException if {@code ranges} or {@code defaultContext} is {@code null}
     * @since 1.7
     */
    public static NumericShaper getContextualShaper(Set<Range> ranges,
                                                    Range defaultContext) {
        if (defaultContext == null) {
            throw new NullPointerException();
        }
        NumericShaper shaper = new NumericShaper(defaultContext, ranges);
        shaper.mask = CONTEXTUAL_MASK;
        return shaper;
    }

    /**
     * Private constructor.
     */
    private NumericShaper(int key, int mask) {
        this.key = key;
        this.mask = mask;
    }

    private NumericShaper(Range defaultContext, Set<Range> ranges) {
        shapingRange = defaultContext;
        rangeSet = EnumSet.copyOf(ranges); // throws NPE if ranges is null.

        // Give precedance to EASTERN_ARABIC if both ARABIC and
        // EASTERN_ARABIC are specified.
        if (rangeSet.contains(Range.EASTERN_ARABIC)
                && rangeSet.contains(Range.ARABIC)) {
            rangeSet.remove(Range.ARABIC);
        }

        // As well as the above case, give precedance to TAI_THAM_THAM if both
        // TAI_THAM_HORA and TAI_THAM_THAM are specified.
        if (rangeSet.contains(Range.TAI_THAM_THAM)
                && rangeSet.contains(Range.TAI_THAM_HORA)) {
            rangeSet.remove(Range.TAI_THAM_HORA);
        }

        rangeArray = rangeSet.toArray(new Range[rangeSet.size()]);
        if (rangeArray.length > BSEARCH_THRESHOLD) {
            // sort rangeArray for binary search
            Arrays.sort(rangeArray,
                    new Comparator<Range>() {
                        public int compare(Range s1, Range s2) {
                            return s1.base > s2.base ? 1 : s1.base == s2.base ? 0 : -1;
                        }
                    });
        }
    }

    /**
     * Converts the digits in the text that occur between start and
     * start + count.
     *
     * @param text  an array of characters to convert
     * @param start the index into <code>text</code> to start
     *              converting
     * @param count the number of characters in <code>text</code>
     *              to convert
     * @throws IndexOutOfBoundsException if start or start + count is
     *                                   out of bounds
     * @throws NullPointerException      if text is null
     */
    public void shape(char[] text, int start, int count) {
        checkParams(text, start, count);
        if (isContextual()) {
            if (rangeSet == null) {
                shapeContextually(text, start, count, key);
            } else {
                shapeContextually(text, start, count, shapingRange);
            }
        } else {
            shapeNonContextually(text, start, count);
        }
    }

    /**
     * Converts the digits in the text that occur between start and
     * start + count, using the provided context.
     * Context is ignored if the shaper is not a contextual shaper.
     *
     * @param text    an array of characters
     * @param start   the index into <code>text</code> to start
     *                converting
     * @param count   the number of characters in <code>text</code>
     *                to convert
     * @param context the context to which to convert the
     *                characters, such as <code>NumericShaper.EUROPEAN</code>
     * @throws IndexOutOfBoundsException if start or start + count is
     *                                   out of bounds
     * @throws NullPointerException      if text is null
     * @throws IllegalArgumentException  if this is a contextual shaper
     *                                   and the specified <code>context</code> is not a single valid
     *                                   range.
     */
    public void shape(char[] text, int start, int count, int context) {
        checkParams(text, start, count);
        if (isContextual()) {
            int ctxKey = getKeyFromMask(context);
            if (rangeSet == null) {
                shapeContextually(text, start, count, ctxKey);
            } else {
                shapeContextually(text, start, count, Range.values()[ctxKey]);
            }
        } else {
            shapeNonContextually(text, start, count);
        }
    }

    /**
     * Converts the digits in the text that occur between {@code
     * start} and {@code start + count}, using the provided {@code
     * context}. {@code Context} is ignored if the shaper is not a
     * contextual shaper.
     *
     * @param text    a {@code char} array
     * @param start   the index into {@code text} to start converting
     * @param count   the number of {@code char}s in {@code text}
     *                to convert
     * @param context the context to which to convert the characters,
     *                such as {@code NumericShaper.Range.EUROPEAN}
     * @throws IndexOutOfBoundsException if {@code start} or {@code start + count} is out of bounds
     * @throws NullPointerException      if {@code text} or {@code context} is null
     * @since 1.7
     */
    public void shape(char[] text, int start, int count, Range context) {
        checkParams(text, start, count);
        if (context == null) {
            throw new NullPointerException("context is null");
        }

        if (isContextual()) {
            if (rangeSet != null) {
                shapeContextually(text, start, count, context);
            } else {
                int key = Range.toRangeIndex(context);
                if (key >= 0) {
                    shapeContextually(text, start, count, key);
                } else {
                    shapeContextually(text, start, count, shapingRange);
                }
            }
        } else {
            shapeNonContextually(text, start, count);
        }
    }

    private void checkParams(char[] text, int start, int count) {
        if (text == null) {
            throw new NullPointerException("text is null");
        }
        if ((start < 0)
                || (start > text.length)
                || ((start + count) < 0)
                || ((start + count) > text.length)) {
            throw new IndexOutOfBoundsException(
                    "bad start or count for text of length " + text.length);
        }
    }

    /**
     * Returns a <code>boolean</code> indicating whether or not
     * this shaper shapes contextually.
     *
     * @return <code>true</code> if this shaper is contextual;
     * <code>false</code> otherwise.
     */
    public boolean isContextual() {
        return (mask & CONTEXTUAL_MASK) != 0;
    }

    /**
     * Returns an <code>int</code> that ORs together the values for
     * all the ranges that will be shaped.
     * <p>
     * For example, to check if a shaper shapes to Arabic, you would use the
     * following:
     * <blockquote>
     * {@code if ((shaper.getRanges() & shaper.ARABIC) != 0) &#123; ... }
     * </blockquote>
     *
     * <p>Note that this method supports only the bit mask-based
     * ranges. Call {@link #getRangeSet()} for the enum-based ranges.
     *
     * @return the values for all the ranges to be shaped.
     */
    public int getRanges() {
        return mask & ~CONTEXTUAL_MASK;
    }

    /**
     * Returns a {@code Set} representing all the Unicode ranges in
     * this {@code NumericShaper} that will be shaped.
     *
     * @return all the Unicode ranges to be shaped.
     * @since 1.7
     */
    public Set<Range> getRangeSet() {
        if (rangeSet != null) {
            return EnumSet.copyOf(rangeSet);
        }
        return Range.maskToRangeSet(mask);
    }

    /**
     * Perform non-contextual shaping.
     */
    private void shapeNonContextually(char[] text, int start, int count) {
        int base;
        char minDigit = '0';
        if (shapingRange != null) {
            base = shapingRange.getDigitBase();
            minDigit += shapingRange.getNumericBase();
        } else {
            base = bases[key];
            if (key == ETHIOPIC_KEY) {
                minDigit++; // Ethiopic doesn't use decimal zero
            }
        }
        for (int i = start, e = start + count; i < e; ++i) {
            char c = text[i];
            if (c >= minDigit && c <= '\u0039') {
                text[i] = (char) (c + base);
            }
        }
    }

    /**
     * Perform contextual shaping.
     * Synchronized to protect caches used in getContextKey.
     */
    private synchronized void shapeContextually(char[] text, int start, int count, int ctxKey) {

        // if we don't support this context, then don't shape
        if ((mask & (1 << ctxKey)) == 0) {
            ctxKey = EUROPEAN_KEY;
        }
        int lastkey = ctxKey;

        int base = bases[ctxKey];
        char minDigit = ctxKey == ETHIOPIC_KEY ? '1' : '0'; // Ethiopic doesn't use decimal zero

        synchronized (NumericShaper.class) {
            for (int i = start, e = start + count; i < e; ++i) {
                char c = text[i];
                if (c >= minDigit && c <= '\u0039') {
                    text[i] = (char) (c + base);
                }

                if (isStrongDirectional(c)) {
                    int newkey = getContextKey(c);
                    if (newkey != lastkey) {
                        lastkey = newkey;

                        ctxKey = newkey;
                        if (((mask & EASTERN_ARABIC) != 0) &&
                                (ctxKey == ARABIC_KEY ||
                                        ctxKey == EASTERN_ARABIC_KEY)) {
                            ctxKey = EASTERN_ARABIC_KEY;
                        } else if (((mask & ARABIC) != 0) &&
                                (ctxKey == ARABIC_KEY ||
                                        ctxKey == EASTERN_ARABIC_KEY)) {
                            ctxKey = ARABIC_KEY;
                        } else if ((mask & (1 << ctxKey)) == 0) {
                            ctxKey = EUROPEAN_KEY;
                        }

                        base = bases[ctxKey];

                        minDigit = ctxKey == ETHIOPIC_KEY ? '1' : '0'; // Ethiopic doesn't use decimal zero
                    }
                }
            }
        }
    }

    private void shapeContextually(char[] text, int start, int count, Range ctxKey) {
        // if we don't support the specified context, then don't shape.
        if (ctxKey == null || !rangeSet.contains(ctxKey)) {
            ctxKey = Range.EUROPEAN;
        }

        Range lastKey = ctxKey;
        int base = ctxKey.getDigitBase();
        char minDigit = (char) ('0' + ctxKey.getNumericBase());
        final int end = start + count;
        for (int i = start; i < end; ++i) {
            char c = text[i];
            if (c >= minDigit && c <= '9') {
                text[i] = (char) (c + base);
                continue;
            }
            if (isStrongDirectional(c)) {
                ctxKey = rangeForCodePoint(c);
                if (ctxKey != lastKey) {
                    lastKey = ctxKey;
                    base = ctxKey.getDigitBase();
                    minDigit = (char) ('0' + ctxKey.getNumericBase());
                }
            }
        }
    }

    /**
     * Returns a hash code for this shaper.
     *
     * @return this shaper's hash code.
     * @see java.lang.Object#hashCode
     */
    public int hashCode() {
        int hash = mask;
        if (rangeSet != null) {
            // Use the CONTEXTUAL_MASK bit only for the enum-based
            // NumericShaper. A deserialized NumericShaper might have
            // bit masks.
            hash &= CONTEXTUAL_MASK;
            hash ^= rangeSet.hashCode();
        }
        return hash;
    }

    /**
     * Returns {@code true} if the specified object is an instance of
     * <code>NumericShaper</code> and shapes identically to this one,
     * regardless of the range representations, the bit mask or the
     * enum. For example, the following code produces {@code "true"}.
     * <blockquote><pre>
     * NumericShaper ns1 = NumericShaper.getShaper(NumericShaper.ARABIC);
     * NumericShaper ns2 = NumericShaper.getShaper(NumericShaper.Range.ARABIC);
     * System.out.println(ns1.equals(ns2));
     * </pre></blockquote>
     *
     * @param o the specified object to compare to this
     *          <code>NumericShaper</code>
     * @return <code>true</code> if <code>o</code> is an instance
     * of <code>NumericShaper</code> and shapes in the same way;
     * <code>false</code> otherwise.
     * @see java.lang.Object#equals(java.lang.Object)
     */
    public boolean equals(Object o) {
        if (o != null) {
            try {
                NumericShaper rhs = (NumericShaper) o;
                if (rangeSet != null) {
                    if (rhs.rangeSet != null) {
                        return isContextual() == rhs.isContextual()
                                && rangeSet.equals(rhs.rangeSet)
                                && shapingRange == rhs.shapingRange;
                    }
                    return isContextual() == rhs.isContextual()
                            && rangeSet.equals(Range.maskToRangeSet(rhs.mask))
                            && shapingRange == Range.indexToRange(rhs.key);
                } else if (rhs.rangeSet != null) {
                    Set<Range> rset = Range.maskToRangeSet(mask);
                    Range srange = Range.indexToRange(key);
                    return isContextual() == rhs.isContextual()
                            && rset.equals(rhs.rangeSet)
                            && srange == rhs.shapingRange;
                }
                return rhs.mask == mask && rhs.key == key;
            } catch (ClassCastException e) {
            }
        }
        return false;
    }

    /**
     * Returns a <code>String</code> that describes this shaper. This method
     * is used for debugging purposes only.
     *
     * @return a <code>String</code> describing this shaper.
     */
    public String toString() {
        StringBuilder buf = new StringBuilder(super.toString());

        buf.append("[contextual:").append(isContextual());

        String[] keyNames = null;
        if (isContextual()) {
            buf.append(", context:");
            buf.append(shapingRange == null ? Range.values()[key] : shapingRange);
        }

        if (rangeSet == null) {
            buf.append(", range(s): ");
            boolean first = true;
            for (int i = 0; i < NUM_KEYS; ++i) {
                if ((mask & (1 << i)) != 0) {
                    if (first) {
                        first = false;
                    } else {
                        buf.append(", ");
                    }
                    buf.append(Range.values()[i]);
                }
            }
        } else {
            buf.append(", range set: ").append(rangeSet);
        }
        buf.append(']');

        return buf.toString();
    }

    /**
     * Returns the index of the high bit in value (assuming le, actually
     * power of 2 >= value). value must be positive.
     */
    private static int getHighBit(int value) {
        if (value <= 0) {
            return -32;
        }

        int bit = 0;

        if (value >= 1 << 16) {
            value >>= 16;
            bit += 16;
        }

        if (value >= 1 << 8) {
            value >>= 8;
            bit += 8;
        }

        if (value >= 1 << 4) {
            value >>= 4;
            bit += 4;
        }

        if (value >= 1 << 2) {
            value >>= 2;
            bit += 2;
        }

        if (value >= 1 << 1) {
            bit += 1;
        }

        return bit;
    }

    /**
     * fast binary search over subrange of array.
     */
    private static int search(int value, int[] array, int start, int length) {
        int power = 1 << getHighBit(length);
        int extra = length - power;
        int probe = power;
        int index = start;

        if (value >= array[index + extra]) {
            index += extra;
        }

        while (probe > 1) {
            probe >>= 1;

            if (value >= array[index + probe]) {
                index += probe;
            }
        }

        return index;
    }

    /**
     * Converts the {@code NumericShaper.Range} enum-based parameters,
     * if any, to the bit mask-based counterparts and writes this
     * object to the {@code stream}. Any enum constants that have no
     * bit mask-based counterparts are ignored in the conversion.
     *
     * @param stream the output stream to write to
     * @throws IOException if an I/O error occurs while writing to {@code stream}
     * @since 1.7
     */
    private void writeObject(ObjectOutputStream stream) throws IOException {
        if (shapingRange != null) {
            int index = Range.toRangeIndex(shapingRange);
            if (index >= 0) {
                key = index;
            }
        }
        if (rangeSet != null) {
            mask |= Range.toRangeMask(rangeSet);
        }
        stream.defaultWriteObject();
    }
}
